Turbine engines used in the power generation industry typically include a compressor section surrounded by a plurality of combustors. The combustors are arranged in a concentric ring around the exterior of the compressor. Compressed air from the compressor section is fed into the combustors where it is mixed with fuel. The fuel-air mixture is then burned in the combustors, and the hot combustion gases are routed into the turbine section of the engine to provide the motive force for running the turbine.
A typical combustor of a turbine engine can include a combustor liner which surrounds the combustion zone where the fuel-air mixture is burned. Some types of combustors include a venturi inside the combustor liner, which is basically a reduced diameter portion of the interior of the combustor liner.
The reduced diameter portion of a combustor liner which forms a venturi often requires specialized cooling to prevent the materials that comprise the venturi from being damaged by the hot combustion gases. This is usually achieved by providing a two-walled structure, where cooling air passes through the annular space between the inner and outer walls of the venturi section to cool the venturi section. Unfortunately, this structure is complex, and can be difficult and expensive to manufacture. In addition, the complexity of the two-walled venturi section often leads to air leaks, which can reduce the overall efficiency of the turbine, as well as lead to the generation of undesirable combustion by-products.